Project Summary/Abstract: The goal of this Phase I project is to develop a first-generation prototype interstitial glucose sensor designed for 3 to 5 day monitoring in diabetic patients. We have previously demonstrated the success of a fluorescence (FRET-based) approach with an improved stable chemistry in extensive in vitro studies and in preliminary in vivo studies and continue to develop this technology for a long-term fully implantable sensor. However, we believe a more immediate solution can be had by leveraging our stable fluorescent assay in a minimally-invasive, short-term, fiber-coupled approach. We will first conduct experiments aimed at engineering and testing a rugged fiber-coupled embodiment of our sensor technology for successful short-term glucose monitoring. We will implement a prototype of a wearable fiber-optic measurement and read-out device. Subsequent to extensive testing of the sensor in vitro, we will place prototype sensors in small and large animals and study their response to varying blood glucose concentrations over several days, followed by host-response analysis of sensor sites. Finally, we will analyze the collected in vivo blood glucose data and develop algorithms for in vivo calibration, accounting for lag-time between sensor response and blood glucose levels. The end result will be a thorough understanding of the functional capability of the fiber-coupled sensor for glucose monitoring in small and large animals over a period of 5-days. If successful, we believe this technology will be poised for evaluation in humans in Phase II. Project Narrative: There is an urgent need for a real-time, continuous, glucose monitoring device for the 100 million people worldwide believed to have diabetes. Maintaining normal levels of blood glucose is the best way to prevent long-term complications of the disease and requires continuous monitoring of glucose levels so that proper adjustments can be made (insulin therapy or diet). We believe the proposed sensor can provide a solution for short-term (3-5 days) continuous monitoring that will be accurate, reliable, and convenient for patient use. [unreadable] [unreadable] [unreadable]